drm: Move format-related helpers to drm_fourcc.c

The drm_crtc.c file is a mess, making the ABI documentation confusing
since all functions are in the same bag. Split the format-related
helpers to a new drm_fourcc.c file.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1465466048-2020-1-git-send-email-laurent.pinchart@ideasonboard.com
diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
new file mode 100644
index 0000000..7f90a39
--- /dev/null
+++ b/include/drm/drm_fourcc.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+#ifndef __DRM_FOURCC_H__
+#define __DRM_FOURCC_H__
+
+#include <linux/types.h>
+#include <uapi/drm/drm_fourcc.h>
+
+void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth, int *bpp);
+int drm_format_num_planes(uint32_t format);
+int drm_format_plane_cpp(uint32_t format, int plane);
+int drm_format_horz_chroma_subsampling(uint32_t format);
+int drm_format_vert_chroma_subsampling(uint32_t format);
+int drm_format_plane_width(int width, uint32_t format, int plane);
+int drm_format_plane_height(int height, uint32_t format, int plane);
+const char *drm_get_format_name(uint32_t format);
+
+#endif /* __DRM_FOURCC_H__ */